This application requests support for trainees and junior faculty to attend the 5th World Congress of Leishmania and Leishmaniasis (WL5) to be held in Brazil in May 2013. Leishmania are protozoan parasites that infect neutrophils, dendritic cells, and macrophages. The active replication and long-term persistence of parasites within specialized vacuoles of macrophages and dendritic cells can lead to dysfunction of host innate and adaptive immunity. Leishmania parasites are transmitted to humans by sand flies and are widely distributed in about 90 tropical and subtropical countries, including certain parts of the U.S. They pose a major public health problem and a risk for millions of people living in endemic areas and entering those areas. The epidemiology of leishmaniasis is extremely diverse, and 20 species of the Leishmania genus are known to be pathogenic for humans. The available anti-Leishmania drugs are far from satisfactory due to high costs, toxicity, or drug resistance. Leishmaniasis is one of the world's principal neglected diseases, for which no effective vaccines are available for any form of the disease. To address these challenges, WL congresses have been held every four years in an endemic country since 1997, and they remain the only international meetings devoted exclusively to Leishmania and leishmaniasis. The primary goal of WL5 is to provide a platform by which investigators working in basic sciences, as well as field-based and translational research have a chance to interact directly. The purpose of this R15 application is to provide travel funds for graduate students, postdoctoral trainees, and junior faculty from the U.S. and other countries to attend WL5. Efforts will be made to provide support for women, minorities, and persons with disabilities and financial limitations. The success and impact of WL5 are ensured by local organizing committees and an International Scientific Committee. This congress and its training opportunities will have a significant impact on the control of infectious diseases and the improvement of global health.